Oxidation Driven Damage on SiC/BN/SiC Ceramic Matrix Composite Aero-Engine Structures: An Iterative Computational...

Area of Science:

• Materials Science
• Mechanical Engineering
• Computational Modeling

Background:

• Ceramic matrix composites (CMCs) present a promising alternative to metallic alloys in aero-engines, offering reduced density and enhanced high-temperature performance.
• However, challenges remain regarding CMC structural integrity, particularly their brittleness and susceptibility to oxidation, which degrades material properties.

Purpose of the Study:

• To model and reproduce experimental oxidation data for CMCs using Fick's law.
• To develop a computational framework for analyzing the coupled phenomena of oxygen diffusion and stiffness degradation in CMCs.

Main Methods:

• Implementation of a Fick's law model in Abaqus to simulate oxidation processes.
• Development of an iterative computational framework to link oxygen diffusion with stiffness degradation.

Main Results:

• Successful modeling of recent oxidation experimental data using Fick's law, providing design parameters for CMCs.
• Demonstration of the coupled relationship between oxidation-induced stiffness degradation and accelerated oxygen diffusion through microcracking.

Conclusions:

• The developed models and computational framework offer valuable tools for designing robust CMC components for demanding applications.
• Understanding the interplay between oxidation and mechanical degradation is crucial for ensuring the long-term structural integrity of CMCs in aero-engines.